Amex also had the lowest default rate in the business for May, at 3.2 percent of balances annualized. Discover and Capital One were next, at 4.82 and 4.84 percent, respectively.

Even the highest default rate reported, the 8.03 percent at the nation’s top card issuer, Bank of America, is back at the point the Charlotte, N.C., bank posted in late 2007, at the start of the recession. The next highest rate, Citibank’s 7.81 percent, remains above what the bank reported prior to the recession, but is below its peak rate of 11.46 percent seen a year ago.

“It continues to paint a good picture,’’ said Michael R. Dean, a managing director at Fitch Ratings who tracks the securities backed by credit card balances. Through the second half of the year, Fitch is expecting both delinquencies to continue to drop.